Instrumented dead shaft for pulley assemblies and the like

Abstract

An instrumented dead shaft is provided for a rotating machine system, such as a drum pulley. The shaft includes bearing support regions for receiving bearings for supporting a rotating element. The shaft also includes at least one sensor assembly, and preferably a number of sensor assemblies for sensing operating parameter of the shaft system. In a preferred configuration, the system includes a rotational speed sensor, temperature sensors, load sensors, and an accelerometer. The speed sensor detects rotational speed of the rotating element and applies an output signal representative thereof to an interface circuit. The temperature sensors provide an indication of the bearing temperatures. The load sensors provide an indication of the strain of the shaft during loading. Output signals from all sensors are transmitted to a control and monitoring circuit via network interfaces. The data links between network interface circuitrys and the sensors are embedded in the shaft. The data links may thus pass beneath the bearing support regions, enabling the sensors to be placed freely along the shaft.

What is claimed is: 
     
       1. A shaft for supporting a machine element in rotation, the shaft being configured to be fixedly and non-rotationally supported on a machine frame and including at least one bearing support region for receiving an antifriction bearing, the antifriction bearing supporting the machine element in rotation on the shaft, the shaft comprising: at least one sensor fixedly supported with respect to the shaft, the sensor generating parameter signals representative of an operating parameter of the shaft, the sensor including a communications link for transmitting the parameter signals to a remote location; and   wherein said at least one sensor comprises a rotational speed sensor fixedly supported on the shaft, the speed sensor generating speed signals representative of the rotational speed of the machine element and transmitting the speed signals to the remote location via the communication link;   an internal channel formed in and extending along the shaft, the communications link being at least partially disposed within the internal channel;   a network interface circuit coupled to the communication link, the network interface circuit being configured to receive the parameter signals and to apply the parameter signals to a monitoring circuit.   
     
     
       2. The shaft of claim 1, wherein said network interface circuit is supported adjacent to the shaft. 
     
     
       3. The shaft of claim 1, further comprising a temperature sensor fixedly supported adjacent to the bearing, the temperature sensor generating a temperature signal representative of the temperature of the bearing, the temperature sensor including a second communications link for transmitting the temperature signal to the remote location. 
     
     
       4. The shaft of claim 3, wherein the second communications link is at least partially disposed within the internal channel. 
     
     
       5. The shaft of claim 3, wherein the shaft further comprises a second internal channel, and wherein the second communications link is at least partially disposed within the second internal channel. 
     
     
       6. The shaft of claim 3, further comprising the network interface circuit coupled to the first and second communications links, the network interface circuit being configured to receive the parameter and temperature signals and to apply the parameter and temperature signals to the monitoring circuit. 
     
     
       7. The shaft of claim 1, wherein the shaft includes first and second bearing support regions for receiving first and second antifriction bearings, respectively, and wherein the shaft comprises first and second temperature sensors disposed within respective first and second recesses in the shaft adjacent to the first and second bearing support regions, the first and second temperature sensors generating temperature signals representative of the temperature of the first and second bearings, respectively. 
     
     
       8. A non-rotatable support shaft for supporting a rotating member in rotation, the shaft being configured to be fixedly supported on a machine frame and including first and second bearing support regions for receiving respective first and second antifriction bearings, the antifriction bearings supporting the rotating member in rotation on the shaft, the shaft comprising: first and second temperature sensors disposed within the shaft adjacent to the first and second bearing support regions, respectively, the first and second temperature sensors generating temperature signals representative of temperatures of the first and second bearings, respectively, the first and second temperature sensors including first and second communications links for transmitting the temperature signals to a remote location; and   a rotational speed sensor fixedly supported thereon, the speed sensor generating speed signals representative of the rotational speed of the rotating member, the speed sensor including a third communications link for transmitting the speed signals to a remote location;   at least one internal channel formed in and extending along the shaft, and wherein the first, second and third communication links are at least partially disposed within the at least one internal channel;   a network interface circuit coupled to the communication link, the network interface circuit being configured to receive the parameter signals and to apply the parameter signals to a monitoring circuit.   
     
     
       9. The shaft of claim 8, wherein said network interface circuit is supported adjacent to the shaft. 
     
     
       10. The shaft of claim 8, wherein the first and second temperature sensors are disposed within first and second internal recesses in the shaft, the first and second recesses at least partially underlying the first and second bearing support regions, respectively. 
     
     
       11. The shaft of claim 8, wherein the at least one internal channel includes first and second internal channels, the internal channels extending from predetermined locations along the shaft to end regions thereof, the first internal channel at least partially underlying the first bearing support region and the second internal channel at least partially underlying the second bearing support region. 
     
     
       12. The shaft of claim 8, wherein the rotating member includes a first end disc configured to be supported on the first bearing and a second end disc configured to be supported on the second bearing, the first end disc carrying at least one metallic extension, and wherein the rotational speed sensor is supported on the shaft in a predetermined location proximate to the first end disc and generates the speed signal by detecting passage of the at least one metallic extension past the predetermined location. 
     
     
       13. The shaft of claim 8, further comprising a load sensor fixedly disposed on the shaft, the load sensor generating a load signal representative of load applied to the shaft, the load sensor including a fourth communications link for transmitting the load signal to the remote location. 
     
     
       14. The shaft of claim 13, wherein the load sensor is disposed intermediate the first and second bearing support regions. 
     
     
       15. A shaft system for supporting a machine element in rotation, the shaft system comprising: a shaft configured to be fixedly and non-rotationally supported on a machine frame and including at least one bearing support region for receiving an antifriction bearing for supporting the machine element in rotation on the shaft;   a plurality of sensors supported on the shaft, each sensor being configured to detect an operating parameter of the shaft system and to generate a corresponding parameter signal representative thereof;   a plurality of communications links, a communications link being coupled to each of the plurality of sensors for transmitting the parameter signals therefrom; and   at least one internal channel formed in and extending along the shaft, and wherein at least one of the communication links is at least partially disposed within the at least one internal channel;   an network interface circuit coupled to the communications links, the interface circuit being configured to receive the parameter signals and to transmit output signals to a remote monitoring circuit.   
     
     
       16. The system of claim 15, wherein the plurality of sensors includes at least a rotational speed sensor. 
     
     
       17. The system of claim 16, wherein the plurality of sensors further includes at least one load sensor. 
     
     
       18. The system of claim 15, further comprising a power supply circuit, the power supply circuit being coupled to at least one of the sensors for supplying power thereto. 
     
     
       19. The shaft of claim 15, wherein said network interface circuit is supported adjacent to the shaft.